Drilling derrick



Fe. 22, 19. T. GLEASON 2,342,139

DRILLING DERRICK Filed May 10, 1941 6 Sheets-Sheet 1 Feb. 22, 1944.

T. GLEASON DRILLING DERRICK Filed May 10, 1941 6 Sheets-Sheet 2 THOMAS GLEASON Feb. 22, 1944. T, GLEASON 2,342,139

. DRILLING DERRICK Filed May 10, 1941 6 Sheets-Sheet 5 Feb. 22, 1944. T. GLEASON 2,342,139

DRILLING DERRICK Filed May 10, 1941 6 Sheets-Sheet 4 T g]. E

T Q- :7- THOMAS GLEASON Feb. 22, 1944. 'r. GLEASON DRILLING DERRICK Filed May 10, 1941 6 Sheets-Sheet 6 3mm HOMAS GLEASON J j f? WWI/WWW Patented Feb. 22, 1944 DRILLING DERRICK Thomas Gleason, Oklahoma City, Okla... assignor to Eccentric Derrick, Inc., Gainesville, Tex.) a corporation of Nevada Application May 10, 1941, Serial No. 392,981

16 Claims.

The present invention relates to 'a derrick for use in the drilling of wells and more particularly to a construction adapted to facilitate the driving of relatively deep oil wells and the like.

The present invention yet more particularly involves improvements upon the invention defined in my copending application Serial No. 357,325, filed September 18, 1940, wherein there is disclosed a so-called eccentric derrick construction involving a fixed but pivoted beam journalled at the top of a slender supporting column. In accordance with the invention, the beam remains relatively fixed in a horizontal position by virtue of a relatively long holding arm anchored to the ground while the opposite arm is relatively short and supports the drilling tackle. In accordance with the invention, the supporting forces are resolved vertically upon the central column which accordingly may be constructed with a relatively attenuated slendemess factor in order to effect a substantial saving in structural material and provide a derrick which is portable and readily assembled and disassembled in any location.

It is an important object of the present invention to provide a derrick as above of the so-called eccentric type having a slender supporting column adapted particularly for rotary drilling wherein the parts are adjustable to maintain the supporting tackle at all times in perfect vertical axial alignment with the well axis. While in my previous construction the derrick automatically adjusts itself to a vertical disposition of the loads when located in predetermined relation to the well, nevertheless it has been found that some lateral divergence of the well casingmay occur. Minor divergence from the desired direction of well drilling may readily be compensated in directions parallel to the beam merely by adjusting the beam to a new fixed position of slight inclination. Nevertheless, with drilling derricks with which I am at present familiar it is impractical to effect lateral adjustment of the tower even in the small degree of displacement necessary.

It is accordingly an important object of the present invention to provide a so-called eccentric derrick as above wherein the beam is rotationally adjustable about the axis of the supporting column for aligning the supporting tackle with the well axis. I

Another important object of the present invention contemplates the provision of an improved hold-down construction for the anchored or rear- "ward extremity of the beam comprising a holding stay antifrictionally embracing the extremity of to be anchored to the ground for resolving the beam-applied stresses in a substantially vertical direction.

LA. further object of the present invention contemplates the provision of an improved eccentric derrick construction as above eliminating the so-called dead line and adapted to compensate for the lateral pull of the so-called fast or running line through the automatic application of an opposed equal and opposite stress in accordance with the variation in application of operative forces applied to the derrick.

It is a yet more specific obiect of the present invention to provide a construction as above wherein the running line is so disposed in cooperation with the extended rear or holding portion of the beam as to exert a stress additive to that of the holding strut or anchor. thus eliminating tion more particularly contemplates carrying the the beam and having diverging portions adapted 5 running line rearwardly and downwardly about a sheave on the beam whereby to exert a downward holding force upon the beam corresponding to the load carried by the derrick.

Another important object of the present invention contemplates the provision of an eccentric derrick as above having an improved pipe racking construction adapted to facilitate the disposition of pipe stands outwardly of the central derrick column and in oppositely inclined relation thereto in such a manner as to eliminate side load. The present pipe racking construction, moreover, provides a guard adapted to retain the pipe stands by providing an embracing guard rail about the vicinity of the well axis.

Among other and further important objects of the present invention are to provide a pipe racking construction as above portable in character and freely releasable from the derrick construction while adapted to be attached thereto at any desired vertical location by simple manipulation; to provide an eccentric derrick construction having an improved beam supporting bearing to which the beam is freely attachable and releasable for rapid assembly and disassembly; to provide an improved mounting construction for the beam bearing; to permit the entire bearing to be rotationally adjusted in a. limited path about the central axis of the column and, more particularly, such. a construction capable of rapid adjustment by a workman at the top of the tower after completion of assembly: and to provide an improved construction wherein each of the parts is capable of being rapidly assembled by merely swinging it into a location where theunits are automatically engageable in operative position.

Yet other and further objects will be apparent from a consideration of the following specification when taken in conjunction withthe accompanying drawings, wherein- Figure 1 is an elevational side view of a drilling derrick embodying the principles of the present invention;

Figure 2 is an elevational front view 'of the derrick shown in Figure 1;

Figure 8 is a sectional view of a column section showing the construction thereof;

Figure 4 is a perspective view of a portion of the upper extremity of the derrick showing the interconnection of the beam with the supporting column;

Figure 5 is a detailed perspective view of the lower portion of the beam shown in inverted relation for purposes of clarity;

Figure 6 is a detailed view taken vertically centrally through the axis of the beam;

Figure 7 is a top plan view of the central column with the beam removed;

Figure 8 is a perspective view of the axle or journal;

Figure 9 is a perspective view of the derrick showing the construction of the pipe racking means; and

Figure 10 is an elevational' side view of'a modifled preferred form of the present invention.

Referring now more particularly to Figures 1 and 2 of the drawings wherein one illustrative embodiment of the present invention is shown in detail, it will be apparent that the invention contemplates the provision of a slender vertical supporting column l8 mounted upon a rigid base i2 and having a beam l4 disposed in adjusted fixed predetermined position horizontally across the upper portion thereof. A tackle I6 is suspended from a short arm on the beam as will be seen, whereas anchor means i8 depend, as shown,

' from the relatively extended arm of the beam.

The tower column is provided with an improved pipe rack construction and a so-called crowsnest construction 22 adjacent the beam. Yet more particularly, the present invention relates to the class of oil drilling derricks and particularly contemplates a construction useable in forming relatively deep wells. Accordingly, therefore, the central column construction l8 may extend to suitable elevation, for example, in the neighborhood of one hundred and twenty feet or thereabove, whereas in accordance with the present invention the transverse dimensions of the column may be relatively small, in the neighborhood of forty inches, for example, providing a slenderness factor in the neighborhood of eighty, for example. It will be appreciated therefore that in the figures the substantially vertical sections of the column have been broken away in order to facilitate illustration. The supporting base l8 preferably comprises a reinforced concrete foundation of suflicient mass to anchor the derrick and, as shown, includes I-beams 24 and 28 anchored to the foundation and to the lower end of the tower ID by means not shown.

Attention is particularly directed to the construction of the tower, shown more clearly in Figures 1, 2, 3 and 9, formed of a plurality of sections and joined together preferably in accordance with the principles set out in my 00- pending application, Serial No. 357,325, filed September 18. 1940. Each of the sections comprises four vertical legs 28 formed of angle iron and spaced at their upper and lower extremities by horizontally extending quadrangularly arranged struts or braces 88. Angularly disposed struts or braces 82 are arranged along each side face of the tower section in inclined relationship, each pair of adjacent struts converging toward a common point of attachment with one of the side legs as at 84. As will be apparent from a consideration of Figures 3 and 9, the inclined braces of each of the side faces of the column are arranged in corresponding vertical relation and each pair of adjacent braces converges toward a point of attachment common with or in the same vertical plane with those in the adjacent face. In other words, it will be seen that at any point of attachment 34 on the upstanding leg 28, two pairs of inclined struts l2 meet at a common juncture. The internal bracing more particularly comprises struts 36 and 38 extending diagonally between diametrically opposite supporting legs 28. Each alternate internal brace 38 extends at right angles to the one below and-is welded to the inner recess of the angle iron supporting legs 28 at points 38 vertically intermediate between the points 34.

- It will be apparent that the foregoing sec tional column construction provides a column of improved strength and rigidity, employing a minimum of material. Each of the sections is therefor relatively light considering its load carrying capacity and in disassembled relationship the sections are extremely portable. It will be understood from the foregoing that the column is assembled by merely bolting the lowermost portion to the base l2 and proceeding to assemble the several sections is superposed relation to the desired elevation and fastening the sections together at the extremities of the vertical legs 28 preferable in accordance with the construction set forth in my copending application Serial No. 357,325, filed September 18, 1940. The topmost section of the tower is provided at its upper extremity with a so-called supporting or water table mounting the beam supporting journal assembly shown in Figures 1, 2 and 4 to 8, inclusive. The so-called water table includes a pair of I-beams 48 extending between and welded to the top extremities of each pair of side legs 28. Laterally extending channels 42 are welded at the extremities of the I-beams 48. Upon the upper webs of the I-beams are mounted a pair of guide tracks 44 including opposed curved flanges 46 and upper inwardly extending retaining flanges 48. Within each of the guide channels or tracks 44 is disposed a bearing block 58 each of the bearing blocks having oppositely extending flanges 52 engaging within the recesses formed by the track flanges 46 and 48. It should be particularly noted that the lateral margins of the bearing block flanges 52 are arcuate and complementary to the inner curvature of the retaining flanges 44. Accordingly, therefore, each bearing block is movable in its track 44 and more particularly in an arcuate path about an axis substantiallyv coincidental with the central axis of the column. The bearing or journal black is held in any position of adjustment by means of the opposed adjustment screws 54 threadedly engaged through the flange 56 of a bracket 58 welded to the upper surfaces of the I-beam 48. Accordingly, therefore, the extremity of each adjustment screw is adapted to abut against the adjacent end of the block I and a lamb nut 58 assures maintenance of the adjustment. It will be apparent from the foregoing that-the relative adjustment of the pair of bearing b1ocks'50 provides for angular adjustment of the beam supporting shaft with respect to the axis of the tower as will hereinafter appear more in detail.

The pair of bearings 50 operatively journal a main shaft 60 as clearly shown in Figures 6 and 7 and each block 50 is provided with a removable cap or cover 62 fastened by machine screws 64. The shaft 60 is axially slotted or splined as at 66.

The beam I4 in the present embodiment comprises a pair of spaced truss constructions shown more in detail in Figures 1, 2 and 4 and consisting of upper and lower horizontal members 68 and 10 respectively, formed of adjacent angle irons welded back to back as shown. Welded inclined braces I2 extend between the upper and lower members as shown. To the end that the beam may be operatively associated with the shaft 60, the lower face of each truss is provided with a plate I4 secured in position as shown in Figures 4 and 5 and has rigidly mounted thereon shaft engaging caps 16. It will be noted that each of these caps comprises a block having. a semicylindrical recess complementary to the upper half of the shaft 60. Each recess is provided with a projecting lip or spline I8 complementary to the slot 66 in the shaft. From the foregoing, it will be evident that with the shaft arranged in its bearings 50 as indicated in Figure 7, the beams I4 may be located automatically in position by merely disposing the recess of the block I6 upon the shaft as shown in Figures 4 and 6 and then applying the caps 80 by means of fasteners 82. It will be apparent that each pair of engaging blocks I6 straddle one of the bearing members 50.

Attention is particularly directed to the fact that each beam truss has a forwardly extending relatively short arm upon which is mounted a sheave construction 80, Figure 1. For purposes of illustration, this assembly comprises a Regan or Emsco crown block disposed centrally between the two beam trusses and supported on a pair of channel members 86. Triangular bearing blocks 88 of the crown block assembly are welded in place upon the channels 86 and journal a shaft 90 rotatably mounting a plurality of pulleys 92. A travelling block unit 94 is suspended from the crown block by means of a wire line 96 having its dead end connected with the crown block as at 98 and preferably centered directly on a vertical line over the well. The fast or running line extremity of the line 96 is carried to a drawworks I00 which may comprise the actuating drum of the drawworks or merely a pulley about which the line passes to a suitable winch. It is important to note that the dead end may join with the crown or running block assembly, depending upon the number of lines and the construction of the sheaves.

Attention is particularly directed to the fact that adjacent the rearmost extremity of the beam I 4 is located a pulley for the anchor line I8, the pulley, designated by the numeral I02, being disposed on the central vertical plan of the beam and mounted on a removable shaft I04. The anchor means further includes a wire line I06 permanently secured to the concrete base I2 as at I08 and having its opposite extremity extending outwardly as at H0 and attached to a deadman or anchor H2 at a predetermined spaced point.

It is thought important to call attention to the fact that for normal purposes a vertical fixed strut extending directly from the center of thesheave I02 to an anchor therebeneath would be sum- 6 cient but in the present embodiment it is noted that the rotary member I 00 is disposed at a slight angle of inclination to the vertical axis of the tower in order to afford adequate working space in the region of the well, as represented by a drill- 10 ing table II 4. Accordingly, therefore, the present construction provides a compensation for the lateral component exerted by the running line. To this end, it will be noted that, while the running line and the inner portion of the hold-down line I06 make an angle with the vertical axis of the tower, the outwardly extending line H0 is oppositely inclined at an angle just sufficient to insure a lateral component equal to twice the components existing in the other two lines. In short,

the three inclined lines are arranged in identically the same plane and the angular disposition of the rearward hold-down line H0 is such as to exactly compensate for stresses in the other inclined lines. The lateral force of line H0 will automatically balance the lateral force of lines I06 and 96 as long as the angle which line IIO makes to the vertical is greater than the angle I06 makes to the vertical. From the foregoing, it-

will be understood by those skilled in the art that the relative angular disposition of the lines may be calculated to substantially or exactly approximate the condition for any tower wherein all lateral stresses are eliminated. A turnbuckle H6 provides for application of a predetermined tension in the hold-down line.

Referring now to Figures 1, 2 and 9, it will be seen that the invention yet more particularly contemplates a portable pipe rack construction which eliminates all danger of falling pipe and comprehends disposal of the pipe stands in oppositely inclined balanced relation. The pipe racking assembly 20 embodies in general a platform supported on suitable framework. It is to be noted that this platform includes a rear laterally extending walk II8 having four forwardly extending platform sections. two internalplatform sections I20 which project forwardly on either side of the tower column, and the outer forwardly extending platform sections I22 at the outer extremities of the rack are spaced outwardly therefrom a substantial distance providing a pair of pipe rack ing recesses I24. A pair of structural members I 26 provide an extension of the forward margins of the walkways I22 providing a recess within which the pipe stands are receivable. It will be apparent from the foregoing that the partly enclosed recesses thus formed ar adapted to accommodate the upper portions of pipe stands indicated by the letter A, the bottom portions of which may rest upon the base I2, as shown, in suitable recesses provided therefor, whereby they incline at a predetermined angle against the inner margin of the platform sections I22. From the foregoing, it will be appreciated that with the pipe stands equally and identically distributed on opposite sides of the column and disposed at equivalent angles of repose, the lateral loads are balanced and eliminate all side stress. In order to further insure predetermined maintenance of the pipe stands in the proper relative locations, the inner margin of each of the platform sections I22 is provided with a plurality of inwardly extending guide arms I28 each capable of receiving a file of pipe stands.

In accordance with the invention. a retaining guard construction I embraces the upper'portions of the pipe stands and comprises a pair of outwardly inclined channel members I02 joined at their outer extremities by a transversely extending channel I and braced by suitable internal struts III. The inner extremities of the channels I02 and the appropriate struts I" are flanged as at I30 for removable attachment to.

the forward margin I20 of the platform.

The details of the frame construction of the platform are not shown herein for the reason that it is thought those skilled in the art in light of the present specification would be able to provide a suitable framework. The various margins of the platform sections, however, are supported in the present embodiment upon suitable angle or channel frame members I40 and the outer margins of the platform sections are provided with a railing construction I42 as shown. Paired inclined braces I and I40 are releasably attached to the tower as at I48 and vertically spaced above the work platform, and a pair of lower braces I50 are clamped at their lowermost ends to the tower below the platform. Attention is directed to the fact that the present working platform and pipe rack is attachable to and removable from the central column or tower as a unit. In short, the inner margins of the platform sections I20 are so proportioned as to freely embrace the tower whereby attachment may be made to. adjacent portions of the column by simple U- or J-bolts I52 extending through the flanges of frame member I00. Similar J-bolts or any other equivalent type of fastening may be used at the extremity of the inclined braces I40 and I50. It is apparent therefore that after assembly of the central column the working platform may be merely hoisted into place either before or after the guard frame I80 has been applied and permanently attached at any desired elevation.

In accordance with the construction, a further working platform or so-called crows-nest 22 is similarly formed and located adjacent the vertical extremity of the central column in the region of the beam supporting bearing, the platform 22 comprising similar platform sections embracing the column on its rearward and lateral side faces and releasably attachable by similar fastening means.

' In accordance with the foregoing description,

. it will be understood that the present invention contemplates a portable drilling derrick particularly useful for rotary drilling and providing a free work space laterally removed from the supporting colunm. It entire structure is composed of unitary sections adapted to be assembled in simple order by means of ordinary gin poles or cranes and wherein the beam and working platforms are freely disposable and attachable in operative position.

The invention additionally provides a construction wherein the supporting forces are at all times resolved vertically upon the central column whereby this element functions at all times in compression alone and eliminating a substantial amount of the structural steel normally necessary in conventional drilling derricks. On the other hand, the character of the construction necessitated by'the enormous loads applicable vertically in deep well drilling is adequate for resisting minor lateral loads of design such for example as wind load. Thus, it will be apprewill be understood that the aeeaiee ofeomospableofsupportingthecolmnnimserytoverticailysupportextremeiosds pressionis der all conditions without the necelity for guy wires.

It is further of importance to note-the psesuit invention provides a construction wherein the parts of the derrick are disposed in the relative position shown while at the same time joined by Journal connections adapted to compensate for mechanical fiexure under load. In other words. the invention is not concerned with parts movable to effect a mechanical operation but merely to assure maintenance of the desired condition of load disposition upon the central axis of the suporting column. In other words, application of load to the travelling block 04 will not result in any appreciable movement of the beam bearing in its journals with the exception of such minute movement to accommodate compression and fie!- ure. Minor adjustment of the turnbuckle II.

may. at times be made to adjust the travelling 7 block 04 forwardly or rearwardly a minor degree where desired. lateral adjustment may be made from the crows nest-22 by merely shifting the bearing blocks 00 upon the water table in opposite directions whereby to arcuately move the beam about the central axis of the column. It

has been found in accordance with the present invention that this last named adjustment is of material importance in view of the fact that the entire working load applied to the short end of the beam must necessarily be accurately aligned in accordance with the principles of the inven- I tion.

Attention is further called to the fact that the rear or elongated arm of the present beam has an effective length substantially equal to four times the length of the forward arm and while the longer arm may be extended or shortened, it is preferred that it possess a length at least in this ratio whereby to decrease the tension on the holding line I00 and enhance the capacity of the structure. In this connection, it should be noted that in accordance with the present construction an increase in force of application to the running line 08 efi'ects a corresponding increase in tension on the line I08. inducing an equal and opposite compensating force adjacent the top of I the derrick. In other words, it will be seen that ciated that the mass of structural material neces- 76 its anchor lines and to the locus of the geometrical center of the crown construction such that the horizontal component of the line I I0 compensates for the lateral forces created in the runllillng line 86 and the forward run of the holding There is shown in Figure 10 a slightly modified form of the present invention wherein the draw works I00 is located to the rear of the derrick and iiffilztlcally beneath the rear margin of the sheave running line 90 is passed about the sheave, I02 and vertically downwardly as at I54. According- 1y, therefore, the problem created by the use of an inclined running line iseliminated and the section of line I exerts a portion at least of the holding force acting against the elongated arm of the beam. It will be appreciated that proceeding in accordance with this modification the ratio between the long and short arms of the beam can in no case be greater than the number of lines in the block tackle and preferably the beam ratio is substantially less. Accordingly;

In accordance with this embodiment, the" mass formed in sections adapted to be readily transported and assembled in any location. The invention, moreover, provides adequate working space and contemplates the resolution of the entire working load upon a vertically extending member with the complete elimination of lateral stresses. tially vertical resolution of all of the material forces at all times and is adapted to adjustment to any fixed positions in accordance with lateral shifting of the well axis during drilling.

The invention provides for a substan-- Obviously the invention is not limited to the specific structural arrangement disclosed herein but is capable of other modifications and changes without departing from the spirit and scope of the present invention.

I claim:

1. A drilling derrick of the class described comprising a vertical column, a laterally extending beam mounted on a horizontal axis at the upper portion of said column and having a relatively short load supporting arm and a relatively long holding arm, work supporting tackle on the relatively short arm, an anchor means pivotally connected with the relatively long arm, said anchor means being fixedly connected with a fixed anchorage, and means for arcuately adjusting said beam pivot means about the vertical axis of the column.

2. A drilling derrick of the class described comprising a vertical colunm, a laterally extending beam mounted on a horizontal axis at the upper portion of said column and having a relatively short load supporting arm and a relatively long holding arm, work supporting tackle on the relatively short arm, an anchor means pivotally connected with the relatively long arm, said anchor means being fixedly connected with the ground, means for arcuately adjusting said beam pivot means about the vertical axisof the column, and means for holding said beam pivot in each position of adjustment.

3. A drilling derrick of the class described comprising a vertical column, a horizontal beam mounted on the upper portion of said colunm about a horizontal, transversely extending axis, said axis substantially intersecting the central vertical axis of the column, said beam having a relatively short work supporting arm projecting laterally to one side of the column and having tackle mounted thereon, fixed anchor means connected with a relatively long arm of the beam and with the ground to hold the beam in horizontal position, and means for adjusting the beam angularly about the. central vertical axis of the column, said .last named means being adapted to positively hold the beam in any adjusted angular position.

4. A drilling derrick of the class described comprising a vertical column, a horizontal beam mounted on the upper portion of said column upon a pivot means extending horizontally and laterally of said beam and having an axis substantially intersecting the central vertical axis of the column, said beam having a relative y short work supporting arm projecting laterally to one side of the column and having tackle mounted axis as a center, means for shifting said shaft supporting means in said path, and operative for positively holding said shaft in adjusted posi- .tion.

5. A drilling derrick of the class described comprising a vertically extending column, a substantially horizontal beam pivotally mounted adjacent the top of said column about a horizontal,

laterally extendingaxis, said beam having a forwardly extending relatively short arm rotationally mounting a tackle at a point laterally spaced from said column, a relatively long arm projecting rearwardly, fixed hold-down means for disposing said beam continuously in horizontal position including a holding member having a pair of inclined holding-down means disposed substantially in the plane of the vertical axis of the beam, one of said holding-down means being inclined forwardly and being adapted for permanentiattachment to the ground and another holding-down means being inclined rearwardly of said plane and being adapted for permanent attachment to the ground.

6. A drilling derrick of the class described comprising a vertically extending column, a sub stantially horizontal beam pivotally mounted adjacent the top of said column about a horizontal, laterally extending axis, said beam having a forwardly extending relatively short arm rotationally mounting a tackle at a point laterally spaced from said column, a relatively long arm projecting rearwardly, fixed hold-down means for disposing said beam continuously in horizontal position including a flexible hold-down member of fixed length engageable with a sheave means adjacent the extremity of said relatively long arm and having sections'extending downwardly in the vertical plane of said beam and being oppositely inclined in said plane and being gdaptgd for permanent attachment with the roun 7. A drilling derrick of the class described stantially horizontal beam pivotally mounted ad- Jacent the top of said column about a horizontal, laterally extending axis, said beam having a forwardly extending relatively short arm rotationally mounting a tackle at a point laterally spaced from said column, a relatively long arm proJecting rearwardly, fixed hold-down means for disposing said beam continuously in horizontal position including a flexible hold-down member disposed substantially in the vertical plane of said beam, and operatively engaging said relatively long arm of the beam at a predetermined point, said flexible member extending downwardly in said vertical plane and being adapted for permanent attachment to the ground at a point forwardly spaced from a line extending vertically through the point of beam attachment, said elongated member having a rearward portion extending downwardly in said plane and being pted for permanent attachment to the ground at a point rearwardly spaced from said vertical line, said beam engagement means being operative to permit the flexible member to relasition including a flexible hold-down member disposed substantially in the vertical plane of said beam, and operatively engaging said relatively long arm. of the beam at a predetermined point, said flexible member extending downwardly in said vertical plane and being adapted for permanent attachment to the ground at a point forwardly spaced from a line extending vertlcaly through the point of beam attachment, said elongated member having a rearward portion extending downwardly in said plane and being adapted for permanent attachment to the ground at a point rearwardly spaced from said vertical line, said beam engagement means being operative to permit the flexible member to relatively move in a direction longitudinally thereof, and means for adjusting said flexible member to a fixed predetermined length adapted to maintain the beam in substantially horizontal position.

9. A drilling derrick of the class described comprising a vertically extending supporting column, a substantially horizontal beam mounted at an upper portion of said column about a horizontal, laterally extending axis, said horizontal axis being disposed to substantially intersect the vertical central axis of the column and the central vertical plane of said beam substantially including said vertical axis, said beam including a relatively short arm projecting laterally and adapted to mount tackle means thereonQsaid beam including a relatively long arm extending rearwardly, hold-down means connected to said relatively long arm and adapted for permanent connection to the ground therebeneath, said holddown means having a predetermined length operative to hold the beam in substantially horizontal position at all times, and a pulley means disposed on said relatively long arm and adapted to receive the running line of said tackle for carrying said running line to a point substantially vertically below said relatively long arm, and means for disposing said beam within a relatively limited arcuate path about the central axis of the column, said last named means being operative to hold said beam in any position of adjustment.

10. A drilling derrick of the class described comprising a vertical supporting column, a substantially horizontal beam pivotally mounted on the upper portion of said column about a horizontal, laterally extending axis and having its central plane disposed to include said axis, anchor means of predetermined length fixed to one arm of said beam and to the ground, tackle disposed on the other arm of said beam at a point laterally spaced from said column, said pivotal means including shaft and bearing means operatively disposed on said column and means to shift said bearings in a path for arcuately moving the beam about the central axis of the column, said last named means being operative to hold the bearing members in adjusted position.

11. In a drilling derrick of the class described, a central vertical column and a beam pivotally mounted on an upper portion of said column, said mounting means including a shaft having a splineway, spaced supportingbearings for said shaft on the column, and paired shaft engaging members on said beam adapted to engage said shaft on opposite sides of each bearing, each shaft engaging member having a spline engaging the spline way of said shaft.

12. In a drilling derrick of the class described, a central vertical column and a beam pivotally mounted on an upper portion of said column, said mounting means including a shaft, a pair of bearing members on the upper portion of said column and embracing said shaft, paired downwardly facing shaft engaging members on said beam, eachpair of shaft engaging members being spaced a distance at least equal to the width of said bearing and being operative to straddle said bearing and operatively engage said shaft for supporting the beam in operative relation, and I a spline connection between said shaft and shaft engaging member.

13. In a drilling derrick of the class described, a central vertical column and a beam pivotally mounted on an upper portionof said column. said mounting means including a shaft, a pair of bearing members on the upper portion of said column and embracing said shaft, paired downwardly facing shaft engaging members on said beam, each pair-of shaft engaging members being spaced at distance at least equal to the width of said bearing and being operative t9 straddle said bearing and operatively engage said shaft for supporting the beam in operative .relation, and means for adjusting said bearings in a path transversely to the axis of said shaft and being operative to hold the bearings in any position of adjustment.

14. A oil drilling derrick of the class described including a vertical central column having substantially vertically extending lateral side faces, a combined working platform and pipe rack for said column having spaced forwardly extending portions defining a recess complementary to the sectional configuration of said column adapted to embrace said column on opposite sides thereof, said sections including means for attaching the platform horizontally to the column, outer platform sections laterally outwardly spaced from said first named sections on opposite sides of the column and providing inwardly facing margins adapted to support the upper portions of pipe stands in inclined vertical relationship, retaining members extending inwardly from the extremities of said outer platform sections toward the column but terminating short of the inner platform sections to provide pipe embracing recesses, and a continuous guard member operatively connected to said outer-platform sections, said guard member extending outwardly from said column and joining said outer platform sections to provide a working space adjacent the column and communicating with said pipe rack.

15. A pipe rack and platform for a drilling tower of the class described comprising a main platform adapted to be disposed horizontally and having a central recess partly surrounding the tower and providing a platform to the rear of said tower, said main platform providing a pair of inner platform. sections extending forwardly from said rear platform section on each side of said tower, outer platform sections extending forwardly from said rear platform of said main platform on opposite sides of said inner platform section and spaced therefrom to provide pipe stand assarso l 7 receiving recesses. and retaining members extending inwardly from said outer platform sections but terminating short of said inner platform sections to retain pipe stands vertically disposed withinsaid recesses.

' 16. A drilling derrick of the class described comprising a vertical column of rectangular cross section in a horizontal plane and a laterally extending beam disposed on a horizontal axis atthe upper portion of said column and having a load ,lo

supporting arm extending laterally outwardly from said column. means adapted to maintain said beam in horizontal position, work supportins tackle depending from the arm, means for racking pipe externally of saidcolumn comprising platform means having an opening therethrough substantially complementary to the horizontal section of said column and adapted partially to em- .brace said column. said platform means having ing inwardly in line with each other to accom- *m'odate vertically-inclined pipe sections in opposed balanced relationship.

mnouss GLEASON. 

